Attic Condensation/Home Inspection, Need advice

[UncleDan]

Hey guys,

So I had a home inspection done yesterday at a house that I'm currently looking at buying. Aside from some half as*ed wiring, the other issue the inspector found was moisture/condensation inside the attic space along the roof boards. I've never heard of this before but it leaves me with concern. He had a damp meter that indicated the boards were damp in some spots.

The attic itself is well ventilated, so I'm not too sure how moisture is accumulating up there but it is. The access to the attic is right in front of the bathroom. Maybe it's steam from the shower..? I don't know.

Do any of you have experience with this? And if so, how did you solve the problem? Another thing I should note is that the inspector couldn't look at the roof itself because it was covered with snow. The roof was done 15 years ago. He's going to go back and look once the snow melts.

I'm just wondering if this is something I should run away from. The rest of the house is pretty much turn key. I'm not looking to take this on if the owners can't get it taken care of.

By the way, I haven't signed the Purchase and Sale agreement yet.

Thanks!

 

[Mr. Mach-ete]

Moisture in the attic in the winter with snow on the roof means leaking roof.

 

[oldmodman]

Moisture in the attic in the winter with snow on the roof means leaking roof.

Absolutely correct.

Assume that you will need to have the roof stripped to the rafters, new sheeting, felt, ice protection within a few feet of the edges, and correct venting.

Plus you will need more insulation installed in the attic before the sheeting goes on. There should not be enough heat escaping through the roof to melt the snow. EVER.

 

[sc98cbra]

As stated above, you need a new roof. Looking at $10k++ easily.

 

[verbal]

The condensation on the sheathing is caused by warm, humid air exiting the living space and meeting the cold roof. I don't know if this necessarily indicates that the roof is bad. They are really two different problems with the humidity problem eventually leading to roof problems.

The humidity problem could be as simple as an under-insulated attic or a bathroom fan venting directly into the attic space. It could also be problems from the basement and lower floors where moist air is migrating to the attic.

What did the inspector have to say about it? I guess you will find out the condition of the roof after he has a chance to walk it. I would not say that either issue is a reason to walk away from the house as long as you are being compensated to fix a potentially bad roof and that the humidity issues can be addressed.

 

[Mr. Mach-ete]

Need pictures of attic space, insulation, outside of home.

 

[fast ford brian]

It sounds like you have a air leak from the living space . If the roof is cold and the heat is getting in the attic it will cause condensation . The roof itself is not insulated so there is where your probably getting the transfer to moisture .

 

[UncleDan]

Absolutely correct.

Assume that you will need to have the roof stripped to the rafters, new sheeting, felt, ice protection within a few feet of the edges, and correct venting.

Plus you will need more insulation installed in the attic before the sheeting goes on. There should not be enough heat escaping through the roof to melt the snow. EVER.

The roof is 15 years old. And, there was no slow melting on it. I asked the home inspector if this could possibly be from a roof leak and he said no, that this was attic condensation.

The attic hatch is right in front of the bathroom. The hatch itself isn't insulated, and the bathroom doesn't have an exhaust fan. I'll bet the shower steam is coming right in there and condensing against the cold roof. Attic itself has plenty of ventilation.

 

[zak88lx]

Are all of the bathroom exhaust fans terminating outside (roof), or are they possibly exhausting straight into the attic?

Edit: Just saw that the bathroom doesn't even have an exhaust fan, which is a problem on its own.

 

[big dad]

I had a similar problem years ago, the culprit was the humidifier that was attached too the furnace was set too high. It eventually ruined the furnace, and the house was only 11 years old. Hope this helps because it's any easy fix providing it hasn't gone on too long which was my case.

 

[UncleDan]

I couldn't extract the pics from the PDF but this is what they found.

 

[hockeylover86]

That spacing looks like where the shingle nails would about be...

 

[UncleDan]

That spacing looks like where the shingle nails would about be...

So is that a roof leak?

 

[hockeylover86]

Hard to tell, it could be if the nails are starting to back out, you would need to inspect closely then check the outside for nail pops

 

[Blackedout]

The condensation on the sheathing is caused by warm, humid air exiting the living space and meeting the cold roof. I don't know if this necessarily indicates that the roof is bad. They are really two different problems with the humidity problem eventually leading to roof problems.

The humidity problem could be as simple as an under-insulated attic or a bathroom fan venting directly into the attic space. It could also be problems from the basement and lower floors where moist air is migrating to the attic.

What did the inspector have to say about it? I guess you will find out the condition of the roof after he has a chance to walk it. I would not say that either issue is a reason to walk away from the house as long as you are being compensated to fix a potentially bad roof and that the humidity issues can be addressed.

^^^^^ 100% AGREE.... The cause is either not enough attic venting or the moisture barrier and or crappy insulating job...

 

[007snake]

I don't see any black plywood at the areas that are arrowed. I agree with what you think. The humidity is escaping from the non-vented bath, warm air goes to cold, which would be the attic and going to the coldest area, which would be the nail penetrations and condensing. Just like you see condensation on the seam between double hung windows- coldest part of the window. Of course I would add an exhaust fan in the bath, (exhausted to the exterior, not the attic), 10 minute auto shut-off timer would be best, insulate the attic hatch- they have nice domes that go above and I don't know where you live, but bring the insulation to current standards.

 

[Mr. Mach-ete]

Do you have a humidifier or a ventless gas fire place? Just curious. Ventless gas fire places have a catalyst that create moisture vapor from combustion gases. The excess moisture is released into the house and will condense on cold surfaces that are below the dew point furthest away from the fire place.

I find the air is so aired, devoid of moisture, in the winter that any steam put off by the shower is immediately dissipated and absorbed into the living space. I have encountered hundreds of bath fans that were vented directly in to the attic of a house, mine included, that caused zero moisture problems to the structure. I'm speaking strictly residential of course.

Most roofs that are leaking have very evident water stain patterns on the roof sheathing, trusses and or rafters. The wood becomes discolored and deformed, plywood starts to buckle, there are even signs of water on the insulation below.

It's been my experience that 90% of a home's moisture issues occur during the spring and summer not so much the winter. (Unless it a leaking roof)

Finally, I would be suspect of the home inspector's little gadget. I find most home inspectors were granted a license after completing a 5 day course at the local community college.

 

[dsrtdukone]

As stated above, you need a new roof. Looking at $10k++ easily.

There's no possible way to estimate the cost of a roof replacement without knowing area, pitch, type of material to be installed, distance from material, etc.

 

[Mr. Mach-ete]

There's no possible way to estimate the cost of a roof replacement without knowing area, pitch, type of material to be installed, distance from material, etc.

:lol:It's called a crystal ball, every member here possess one. That's what makes us so great here on SVTP.:lol:

 

[Adamn]

If the shingles are 15 years old plan on replacing them in the next 5 years if it doesn't need it now. Even if there is 30 year shingles on the house you will never get 30 years out of them it's typically more like 20